浏览器中的cookie

/*下面代码来自《Javascript高级程序设计》，封装了浏览器中常用cookie操作*/
cookieUtil = {
    //获取cookie
    "get" : function(name){
        if(typeof name !== "string"){
            return "";
        }
        
        var cookieName = encodeURIComponent(name) + '=',
            cookieStart = document.cookie.indexOf(cookieName),
            cookieValue = "",
            cookieEnd = -1;
        if(cookieStart > -1){
            cookieEnd = document.cookie.indexOf(";", cookieStart);
            if(cookieEnd == -1){
                cookieEnd = document.cookie.length;
            }
            cookieValue = document.cookie.slice(cookieStart + cookieName.length, cookieEnd);
        }
        return cookieValue;
    },
    //设置cookie
    "set" : function(name, value, expires, maxAge, path, domain, secure){
        var cookieText = encodeURIComponent(name) + '=' + encodeURIComponent(value);
        if(expires instanceof Date){
            cookieText += "; expires=" + expires.toGTMString();
        }
        if(maxAge){
            cookieText += "; max-age=" + maxAge;  
        }
        if(path){
            cookieText += "; path=" + path;
        }
        if(domain){
            cookieText += "; domain=" + domain;
        }
        if(secure){
            cookieText += "; secure";
        }
        document.cookie = cookieText;
    },
    //清除cookie
    "unset" : function(name, expires, maxAge, path, domain, secure){
        this.set(name, "", new Date(0), 0, path, domain, secure);
    }
};

/*
cookie
1.document.cookie
2.一个名值对（加与其相关的配置）即为一个cookie
3.cookie的配置信息
    expires    GTM时间，过期时间，设置cookie在某月某日某时刻到期
    max-age    秒，cookie在多少秒后过期
    domain
    path
    secure     设置secure后只有在协议为https是才能使用cookie
    httpOnly   
    在浏览器中使用时，配置信息必须与名值对同时设置
4.浏览器中通过document.cookie访问到的cookie不包含cookie的配置信息
5.多个cookie之间，cookie与其配置之间用引号加一个空格隔开
6.最好为cookie的键和值使用url编码
7.如果没有为cookie设置expires或max-age，则cookie被视为会话cookie，当浏览器关闭后cookie即被删除，但关闭标签页cookie不会被删除
8.max-age的优先级高于expires

*/